Inbred corn line LH263

ABSTRACT

A novel inbred corn line, designated LH263, is disclosed. The invention relates to the seeds of inbred corn line LH263, to the plants of inbred corn line LH263 and to methods for producing a corn plant produced by crossing the inbred line LH263 with itself or another corn line. The invention further relates to hybrid corn seeds and plants produced by crossing the inbred line LH263 with another corn line.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinctive corn inbred line,designated LH263.

The goal of plant breeding is to combine in a single variety/hybridvarious desirable traits. For field crops, these traits may includeresistance to diseases and insects, tolerance to heat and drought,reducing the time to crop maturity, greater yield, and better agronomicquality. With mechanical harvesting of many crops, uniformity of plantcharacteristics such as germination and stand establishment, growthrate, maturity, and fruit size is important.

There are numerous steps in the development of any novel, desirableplant germplasm. Plant breeding begins with the analysis and definitionof problems and weaknesses of the current germplasm, the establishmentof program goals, and the definition of specific breeding objectives.The next step is selection of germplasm that possess the traits to meetthe program goals. The goal is to combine in a single variety or hybridan improved combination of desirable traits from the parental germplasm.These important traits may include higher yield, resistance to diseasesand insects, better stalks and roots, tolerance to drought and heat, andbetter agronomic quality.

Choice of breeding or selection methods depends on the mode of plantreproduction, the heritability of the trait(s) being improved, and thetype of cultivar used commercially (e.g., F₁ hybrid cultivar, purelinecultivar, etc.). For highly heritable traits, a choice of superiorindividual plants evaluated at a single location will be effective,whereas for traits with low heritability, selection should be based onmean values obtained from replicated evaluations of families of relatedplants. Popular selection methods commonly include pedigree selection,modified pedigree selection, mass selection, and recurrent selection.

The complexity of inheritance influences choice of the breeding method.Backcross breeding is used to transfer one or a few favorable genes fora highly heritable trait into a desirable cultivar. This approach hasbeen used extensively for breeding disease-resistant cultivars. Variousrecurrent selection techniques are used to improve quantitativelyinherited traits controlled by numerous genes. The use of recurrentselection in self-pollinating crops depends on the ease of pollination,the frequency of successful hybrids from each pollination, and thenumber of hybrid offspring from each successful cross.

Each breeding program should include a periodic, objective evaluation ofthe efficiency of the breeding procedure. Evaluation criteria varydepending on the goal and objectives, but should include gain fromselection per year based on comparisons to an appropriate standard,overall value of the advanced breeding lines, and number of successfulcultivars produced per unit of input (e.g., per year, per dollarexpended, etc.).

Promising advanced breeding lines are thoroughly tested and compared toappropriate standards in environments representative of the commercialtarget area(s) for three years at least. The best lines are candidatesfor new commercial cultivars; those still deficient in a few traits areused as parents to produce new populations for further selection.

These processes, which lead to the final step of marketing anddistribution, usually take from eight to 12 years from the time thefirst cross is made. Therefore, development of new cultivars is atime-consuming process that requires precise forward planning, efficientuse of resources, and a minimum of changes in direction.

A most difficult task is the identification of individuals that aregenetically superior, because for most traits the true genotypic valueis masked by other confounding plant traits or environmental factors.One method of identifying a superior plant is to observe its performancerelative to other experimental plants and to a widely grown standardcultivar. If a single observation is inconclusive, replicatedobservations provide a better estimate of its genetic worth.

The goal of corn breeding is to develop new, unique and superior corninbred lines and hybrids. The breeder initially selects and crosses twoor more parental lines, followed by repeated selfing and selection,producing many new genetic combinations. The breeder can theoreticallygenerate billions of different genetic combinations via crossing,selfing and mutations. The breeder has no direct control at the cellularlevel. Therefore, two breeders will never develop the same line, or evenvery similar lines, having the same corn traits.

Each year, the plant breeder selects the germplasm to advance to thenext generation. This germplasm is grown under unique and differentgeographical, climatic and soil conditions, and further selections arethen made, during and at the end of the growing season. The inbred lineswhich are developed are unpredictable. This unpredictability is becausethe breeder's selection occurs in unique environments, with no controlat the DNA level (using conventional breeding procedures), and withmillions of different possible genetic combinations being generated. Abreeder of ordinary skill in the art cannot predict the final resultinglines he develops, except possibly in a very gross and general fashion.The same breeder cannot produce the same line twice by using the exactsame original parents and the same selection techniques. Thisunpredictability results in the expenditure of large research money todevelop a superior new corn inbred line.

The development of commercial corn hybrids requires the development ofhomozygous inbred lines, the crossing of these lines, and the evaluationof the crosses. Pedigree breeding and recurrent selection breedingmethods are used to develop inbred lines from breeding populations.Breeding programs combine desirable traits from two or more inbred linesor various broad-based sources into breeding pools from which inbredlines are developed by selfing and selection of desired phenotypes. Thenew inbreds are crossed with other inbred lines and the hybrids fromthese crosses are evaluated to determine which have commercialpotential.

Pedigree breeding is used commonly for the improvement ofself-pollinating crops or inbred lines of cross-pollinating crops. Twoparents which possess favorable, complementary traits are crossed toproduce an F₁. An F₂ population is produced by selfing one or several F₁'s or by intercrossing two F₁ 's (sib mating). Selection of the bestindividuals is usually begun in the F₂ population; then, beginning inthe F₃, the best individuals in the best families are selected.Replicated testing of families, or hybrid combinations involvingindividuals of these families, often follows in the F₄ generation toimprove the effectiveness of selection for traits with low heritability.At an advanced stage of inbreeding (i.e., F₆ and F₇), the best lines ormixtures of phenotypically similar lines are tested for potentialrelease as new cultivars.

Mass and recurrent selections can be used to improve populations ofeither self- or cross-pollinating crops. A genetically variablepopulation of heterozygous individuals is either identified or createdby intercrossing several different parents. The best plants are selectedbased on individual superiority, outstanding progeny, or excellentcombining ability. The selected plants are intercrossed to produce a newpopulation in which further cycles of selection are continued.

Backcross breeding has been used to transfer genes for a simplyinherited, highly heritable trait into a desirable homozygous cultivaror inbred line which is the recurrent parent. The source of the trait tobe transferred is called the donor parent. The resulting plant isexpected to have the attributes of the recurrent parent (e.g., cultivar)and the desirable trait transferred from the donor parent. After theinitial cross, individuals possessing the phenotype of the donor parentare selected and repeatedly crossed (backcrossed) to the recurrentparent. The resulting plant is expected to have the attributes of therecurrent parent (e.g., cultivar) and the desirable trait transferredfrom the donor parent.

Descriptions of other breeding methods that are commonly used fordifferent traits and crops can be found in one of several referencebooks (e.g., Allard, 1960; Simmonds, 1979; Sneep et al., 1979; Fehr,1987).

Proper testing should detect any major faults and establish the level ofsuperiority or improvement over current cultivars. In addition toshowing superior performance, there must be a demand for a new cultivarthat is compatible with industry standards or which creates a newmarket. The introduction of a new cultivar will incur additional coststo the seed producer, the grower, processor and consumer; for specialadvertising and marketing, altered seed and commercial productionpractices, and new product utilization. The testing preceding release ofa new cultivar should take into consideration research and developmentcosts as well as technical superiority of the final cultivar. Forseed-propagated cultivars, it must be feasible to produce seed easilyand economically.

Once the inbreds that give the best hybrid performance have beenidentified, the hybrid seed can be reproduced indefinitely as long asthe homogeneity of the inbred parent is maintained. A single-crosshybrid is produced when two inbred lines are crossed to produce the F₁progeny. A double-cross hybrid is produced from four inbred linescrossed in pairs (AxB and CxD) and then the two F₁ hybrids are crossedagain (AXB) x (CxD). Much of the hybrid vigor exhibited by F₁ hybrids islost in the next generation (F2). Consequently, seed from hybridvarieties is not used for planting stock.

Corn is an important and valuable field crop. Thus, a continuing goal ofplant breeders is to develop stable, high yielding corn hybrids that areagronomically sound. The reasons for this goal are obviously to maximizethe amount of grain produced on the land used and to supply food forboth animals and humans. To accomplish this goal, the corn breeder mustselect and develop corn plants that have the traits that result insuperior parental lines for producing hybrids. This requiresidentification and selection of genetically unique individuals which ina segregating population occur as the result of a combination ofcrossover events plus the independent assortment of specificcombinations of alleles at many gene loci which results in specificgenotypes. Based on the number of segregating genes, the frequency ofoccurrence of any individual with a specific genotype is less than 1 in10,000. Thus, even if the entire genotype of the parents has beencharacterized and the desired genotype is known, only a few, if any,individuals having the desired genotype may be found in a large F₂ or S₀population. Typically, however, the genotype of neither the parents northe desired genotype is known in any detail.

SUMMARY OF THE INVENTION

According to the invention, there is provided a novel inbred corn line,designated LH263. This invention thus relates to the seeds of inbredcorn line LH263, to the plants of inbred corn line LH263 and to methodsfor producing a corn plant produced by crossing the inbred line LH263with itself or another corn line. This invention further relates tohybrid corn seeds and plants produced by crossing the inbred line LH263with another corn line.

DEFINITIONS

In the description and tables which follow, a number of terms are used.In order to provide a clear and consistent understanding of thespecification and claims, including the scope to be given such terms,the following definitions are provided:

Predicted RM. This trait for a hybrid, predicted relative maturity (RM),is based on the harvest moisture of the grain. The relative maturityrating is based on a known set of checks and utilizes conventionalmaturity systems such as the Minnesota Relative Maturity Rating System.

MN RM. This represents the Minnesota Relative Maturity Rating (MN RM)for the hybrid and is based on the harvest moisture of the grainrelative to a standard set of checks of previously determined MN RMrating. Regression analysis is used to compute this rating.

Yield (Bushels/Acre). The yield in bushels/acre is the actual yield ofthe grain at harvest adjusted to 15.5% moisture.

Moisture. The moisture is the actual percentage moisture of the grain atharvest.

GDU Silk. The GDU silk (=heat unit silk) is the number of growing degreeunits (GDU) or heat units required for 50% of plants of an inbred lineor hybrid to be in silk from the time of emergence.

GDU Pollen. The GDU pollen (=heat unit pollen) is the number of growingdegree units (GDU) or heat units required for 50% of plants of an inbredline or hybrid to be in pollen from the time of emergence.

Growing degree units are calculated by the Barger Method, where the heatunits for a 24-hour period are: ##EQU1## The highest maximum used is 86°F. and the lowest minimum used is 50° F. For each hybrid, it takes acertain number of GDUs to reach various stages of plant development.GDUs are a way of measuring plant maturity.

Stalk Lodging. This is the percentage of plants that stalk lodge, i.e.,stalk breakage, as measured by either natural lodging or pushing thestalks determining the percentage of plants that break off below theear. This is a relative rating of a hybrid to other hybrids forstandability.

Root Lodging. The root lodging is the percentage of plants that rootlodge; i.e., those that lean from the vertical axis at an approximate30° angle or greater would be counted as root lodged.

Plant Height. This is a measure of the height of the hybrid from theground to the tip of the tassel, and is measured in centimeters.

Ear Height. The ear height is a measure from the ground to the ear nodeattachment, and is measured in centimeters.

Dropped Ears. This is a measure of the number of dropped ears per plot,and represents the percentage of plants that dropped an ear prior toharvest.

DETAILED DESCRIPTION OF THE INVENTION

Inbred corn line LH263 is a yellow dent corn with superiorcharacteristics, and provides an excellent parental line in crosses forproducing first generation (F₁) hybrid corn. This inbred is best adaptedfor the Northcentral region of the United States.

Inbred corn line LH263 was developed from the cross LH51×LH211 byselfing and using the ear-row pedigree method of breeding. Yield, stalkquality, root quality, ear retention, disease tolerance, late plantgreenness, late plant intactness, ear retention, pollen sheddingability, silking ability and corn borer tolerance were the criteria usedto determine the rows from which ears were selected. Selfing andselection were practiced within the above F₁ cross for seven generationsin the development of LH263. During the development of the line, crosseswere made to inbred testers for the purpose of estimating the line'sgeneral and specific combining ability, and evaluations were run by theWilliamsburg, Iowa Research Station. The inbred was evaluated further asa line and in numerous crosses by the Willaimsburg, Iowa ResearchStation and other research stations across the Corn Belt. The inbred hasproven to have a very good combining ability in hybrid combinations andto produce hybrids which are better adapted for several environmentswithin the Corn Belt.

The inbred has shown uniformity and stability for all traits, asdescribed in the following variety description information. It has beenself-pollinated and ear-rowed a sufficient number of generations, withcareful attention to uniformity of plant type to ensure homozygosity andphenotypic stability. The line has been increased both by hand andsibbed in isolated fields with continued observation for uniformity. Novariant traits have been observed or are expected in LH263.

Inbred corn line LH263, being substantially homozygous, can bereproduced by planting seeds of the line, growing the resultant cornplants under self-pollinating or sib-pollinating conditions withadequate isolation and harvesting the resultant seed, using techniquesfamiliar to the agricultural arts.

Inbred corn line LH263 has the following morphologic and othercharacteristics (based primarily on data collected at Williamsburg,Iowa). The number in each parenthesis corresponds to the standarddeviation in a sample size of 50, unless marked by an asterisk for whichcase the sample size is 15.

VARIETY DESCRIPTION INFORMATION

A. Maturity

INBRED=LH263

Developed In: Northcentral Region of Corn Belt

Heat Unit Silk: 1615.5 93 days!

Heat Unit Pollen: 1558.5 91 days! ##EQU2##

B. Plant Characteristics

Plant height (to tassel tip): 204.4 cm (6.3)

Ear height (to base of top ear): 84.3 cm (8.67)

Length of top ear internode: 15.8 cm (1.56)

Average Number of tillers: 0.0 (0)

Average Number of ears per stalk: 1.1 (0.0)

Anthocyanin of Brace Roots: Absent

C. Leaf

Width (widest point of ear node leaf): 8.5 cm (0.58)

Length (ear node leaf): 62.7 cm (3.27)

Number of leaves above top ear: 5 (0.44)

Leaf angle: 32° (6.74) (measured from 2nd leaf above ear at anthesis tostalk above leaf)

Color: medium green (Munsell code: 5GY 4/4)

Leaf sheath pubescence: 4 (rated on scale from 1=none to 9=like peachfuzz)

Marginal waves: 4 (rated on scale from 1=none to 9=many)

Longitudinal creases: 3 (rated on scale from 1=none to 9=many)

D. Tassel

Number of primary lateral branches: 8 (1.29)

Branch angle from central spike: 20° (8.20)

Tassel length (from top leaf collar to tassel tip): 45.3 cm (2.40)

Pollen shed: 7 (rated on scale from 0=male sterile to 9=heavy shed)

Anther color: yellow (Munsell code: 2.5GY 8/8)

Glume color: medium green (Munsell code: 5GY 5/6)

Bar glumes: Absent

E. Ear (Unhusked Data)

Silk color (3 days after emergence): light green (Munsell code: 2.5GY8/8)

Fresh husk color (25 days after 50% silking): light green (Munsell code:2.5GY 7/6)

Dry husk color (65 days after 50% silking): buff (Munsell code: 7.5YR7/4)

Position of ear at dry husk stage: Pendent

Husk tightness: 5 (rated on scale from, 1=very loose to 9=very tight)

Husk extension: Medium (<8 cm)

F. Ear (Husked Data)

Length: 17.0 cm (1.73)

Diameter at midpoint: 36.8 mm (2.20)

Weight: 83.3 gm (19.78)

Number of kernel rows: 10 (0.70)

Kernel rows: Distinct

Row Alignment: straight

Shank length: 12.9 cm (3.34)

Taper of Ear: Average

G. Kernel (Dried)

Length: 10.3 mm (0.66)

Width: 9.5 mm (0.58)

Thickness: 4.0mm (0.0)

% Rounds (shape grade): 34.7 (5.16)*

Aleurone color pattern: Homozygous

Aleurone color: white

Hard endosperm color: yellow

Endosperm type: Normal starch

Gm Weight/100 seeds (unsized): 33.2 gm (0.45)*

H. Cob

Diameter at midpoint: 26.1 mm (1.70)

Color: Red (Munsell code: 10R 5/6)

I. Disease Resistance (rated from 1=most susceptible to 9=mostresistant)

Northern leaf blight (Exserohilum turcicum) race 2: 8

Southern leaf blight (Bipolaris maydis) race 0: 8

H. carbonum race 3: 9

J. Agronomic Traits

Stay green (at 65 days after anthesis): 6 (rated on scale from 1=worstto 9=excellent)

% Dropped ears (at 65 days after anthesis): 0.0

% Pre-anthesis brittle snapping: 0.0

% Pre-anthesis root lodging: 0.0

% Post-anthesis root lodging (at 65 days after anthesis): 0.0

This invention is also directed to methods for producing a corn plant bycrossing a first parent corn plant with a second parent corn plant,wherein the first or second corn plant is the inbred corn plant from theline LH263. Further, both first and second parent corn plants may befrom the inbred line LH263. Therefore, any methods using the inbred cornline LH263 are part of this invention: selfing, backcrosses, hybridbreeding, and crosses to populations. Any plants produced using inbredcorn line LH263 as a parent are within the scope of this invention.Advantageously, the inbred corn line is used in crosses with other cornvarieties to produce first generation (F₁) corn hybrid seed and plantswith superior characteristics.

As used herein, the term "plant" includes plant cells, plantprotoplasts, plant cell of tissue culture from which corn plants can beregenerated, plant calli, plant clumps, and plant cells that are intactin plants or parts of plants, such as embryos, pollen, flowers, kernels,ears, cobs, leaves, husks, stalks, root, root tips, anthers, silk andthe like.

Tissue culture of corn is described in U.S. Pat. Nos. 4,665,030,4,806,483 and 4,843,005, incorporated herein by reference. Corn tissueculture procedures are also described in Green and Rhodes, "PlantRegeneration in Tissue Culture of Maize", Maize for Biological Research(Plant Molecular Biology Association, Charlottesville, Va. 1982), at367-372. Thus, another aspect of this invention is to provide for cellswhich upon growth and differentiation produce the inbred line LH263.

Transformation of corn is described in U.S. Pat. Nos. 5,384,253,5,489,520, 5,538,877 and 5,550,318, incorporated herein by reference.Corn transformation is also described in Prioli and Sondahl, "PlantRegeneration and Recovery of Fertile Plants from Protoplasts of Maize(Zea Mays L.)", Bio/technology 7:589-594 (1989); Shillito et al.,"Regeneration of Fertile Plants from Protoplasts of Elite Inbred Maize",Bio/technology 7:581-587 (1989). Thus, another aspect of this inventionis to provide inbred line LH263 which contains a heterologous gene.

LH263 is most similar to parental line LH211. However the mostdistinguishing difference is the number of kernel rows per ear. Thenumber of kernel rows per ear of LH263 is less than the number of kernelrows per ear of LH211. The data for kernel rows per ear for LH263 andLH211 with 50 observations from two different planting dates during the1996 growing season are as follows:

A) Average: LH263: 10.000 Standard Deviation: LH263: 0.904

LH211: 12.760 LH211: 0.981

Statistic: T=-14.64 (DF=97) Probability Value: 0.000

B) Average: LH263: 9.920 Standard Deviation: LH263: 0.695

LH211: 12.360 LH211: 1.12

Statistic: T=-13.08 (DF=81) Probability Value: 0.000

In both cases, the data suggests a significant difference at the 1%probability level according to a paired T-test. The means show that onaverage LH263 has less kernel rows per ear than LH211.

LH263 is a medium late season field corn inbred line that flowers one totwo says earlier than LH51. It is a very good pollinator, but is notsuitable for use as a seed parent. LH263 hybrids are higher yielding andaverage aproximately 1.5% less harvest moisture than comparable LH51hybrids. The ears of LH263 hybrids are attractive due to theirconsistent, large size and moderately high placement on the stalk. LH263hybrids display a robust appearance early in the season, while later inthe growing season staygreen is only average. Corn borer removal ofplant tops is most severe in LH263 crosses than comparable LH51 crosses.Lighter grain test weight may be of concern for some LH263 hybrids. Rootstrength of LH263 hybrids is excellent. LH263 hybrids are slightlyhigher yielding and 1-2% lower in harvest moisture than their LH51 andLH216 counterparts. LH263 hybrids have a long ear style.

TABLES

In the tables that follow, the traits and characteristics of inbred cornline LH263 are given in hybrid combination. The data collected on inbredcorn line LH263 is presented for the key characteristics and traits. Thetables present yield test information about LH263. LH263 was tested inseveral hybrid combinations at eight locations, with two or threereplications per location. Information about these hybrids, as comparedto several check hybrids, is presented.

The first pedigree listed in the comparison group is the hybridcontaining LH263. Information for the pedigree includes:

1. Mean yield of the hybrid across all locations.

2. A mean for the percentage moisture (% M) for the hybrid across alllocations.

3. A mean of the yield divided by the percentage moisture (Y/M) for thehybrid across all locations.

4. A mean of the percentage of plants with stalk lodging (% SL) acrossall locations.

5. A mean of the percentage of plants with root lodging (% RL) acrossall locations.

6. A mean of the percentage of plants with dropped ears (% DE).

7. The number of locations indicates the locations where these hybridswere tested together.

The series of hybrids listed under the hybrid containing LH263 areconsidered check hybrids. The check hybrids are compared to hybridscontaining the inbred LH263.

The (+) or (-) sign in front of each number in each of the columnsindicates how the mean values across plots of the hybrid containinginbred LH263 compare to the check crosses. A (+) or (-) sign in front ofthe number indicates that the mean of the hybrid containing inbred LH263was greater or lesser, respectively, than the mean of the check hybrid.For example, a +4 in yield signifies that the hybrid containing inbredLH263 produced 4 bushels more corn than the check hybrid. If the valueof the stalks has a (-) in front of the number 2, for example, then thehybrid containing the inbred LH263 had 2% less stalk lodging than thecheck hybrid.

                                      TABLE 1                                     __________________________________________________________________________    Overall Comparisons of                                                        LH195 × LH263 Hybrids Vs. Check Hybrids                                           Mean                Plnt                                                                             Ear                                          Hybrid    Yield                                                                             % M                                                                              Y/M                                                                              % SL                                                                             % RL                                                                             % DE                                                                              Hgt                                                                              Hgt                                          __________________________________________________________________________    LH195 × LH263                                                                     179 18.68                                                                            9.59                                                                              3  0  0  104                                                                              48                                           (at 12 Loc's, 1995)                                                           as Compared to:                                                               LH195 × LH216                                                                     +4  -2.02                                                                            +1.12                                                                             0  0  0  -5  0                                           LH200 × LH216                                                                     -2  -1.09                                                                            +.43                                                                             +1 -1  0  -5 -1                                           LH197 × LH51                                                                      -5   -.09                                                                            -.20                                                                              0 -1  0  -3 -2                                           LH195 × LH212                                                                     +3   +.76                                                                            -.22                                                                             -2 -2 -1  -6  0                                           LH195 × LH59                                                                      +14 +1.22                                                                            +.15                                                                             -2 -2 -1  -1  0                                           __________________________________________________________________________

                                      TABLE 2                                     __________________________________________________________________________    Overall Comparisons of                                                        LH231 × LH263 Hybrids Vs. Check Hybrids                                           Mean                Plnt                                                                             Ear                                          Hybrid    Yield                                                                             % M                                                                              Y/M                                                                              % SL                                                                             % RL                                                                             % DE                                                                              Hgt                                                                              Hgt                                          __________________________________________________________________________    LH231 × LH263                                                                     165 17.07                                                                            9.66                                                                              4 1  0   107                                                                              41                                           (at 10 Loc's, 1995)                                                           as compared to:                                                               LH231 × LH51                                                                      +6  -1.55                                                                            +1.11                                                                            -1 0  0   0  -4                                           LH231 × LH185                                                                     -10 -.88                                                                             -.06                                                                             -2 0  0   +1 +3                                           LH197 × LH59                                                                      +7  +.16                                                                             +.29                                                                             -2 0  -1  -2 0                                            LH198 × LH185                                                                     +7  +.63                                                                             +.05                                                                             -2 0  0   -4 -2                                           LH195 × LH59                                                                      +1  +.66                                                                             -.36                                                                             -1 0  0   +16                                                                              -2                                           LH200 × LH59                                                                      +2  +.84                                                                             -.34                                                                             -3 -2 0   -2 -3                                           __________________________________________________________________________

                                      TABLE 3                                     __________________________________________________________________________    Overall comparisons of                                                        LH200 LH263 Hybrids Vs. Check Hybrids                                                   Mean                Plnt                                                                             Ear                                          Hybrid    Yield                                                                             % M                                                                              Y/M                                                                              % SL                                                                             % RL                                                                             % DE                                                                              Hgt                                                                              Hgt                                          __________________________________________________________________________    LH200 × LH263                                                                     173 17.64                                                                            9.80                                                                              4  1  0  112                                                                              50                                           (at 9 Loc's, 1995)                                                            as compared to:                                                               LH200 × LH216                                                                      +3 -2.00                                                                            +1.14                                                                            +2 -1 -1  -2 +1                                           LH231 × LH185                                                                      +4  +.31                                                                            +.08                                                                             -2 -1  0  +3 +10                                          LH200 × LH212                                                                      +3 +1.05                                                                            -.45                                                                             -2  0 -1  -3 +4                                           LH198 × LH185                                                                      +2 +1.13                                                                            -.54                                                                             +1 -1  0  +2 +8                                           LH195 × LH186                                                                     +11 +1.47                                                                            -.23                                                                              0 +1  0   0 +6                                           LH200 × LH186                                                                     +13 +1.77                                                                            -29                                                                              -1 +1 -1   0 +7                                           LH235 × LH186                                                                     +10 +2.13                                                                            -.67                                                                              0 +1 -1  -6 +2                                           LH198 × LH186                                                                     +16 +2.25                                                                            -.37                                                                              0  0 -1  -2 +3                                           __________________________________________________________________________

Initial disease ratings of several inred lines were taken atWilliamsburg, Iowa in 1995 and are as follows in which 0=excellent and9=poor.

    ______________________________________                                        Disease    LH263   LH51   LH59 LH168 LH172 LH212                              ______________________________________                                        Carbonum   0.0     0.2    0.5  1.0   0.4   1.3                                Northern (race2)                                                                         1.0     1.1    1.6  3.8   4.0   2.3                                Soutern    1.0     1.1    1.5  4.3   3.5   1.7                                ______________________________________                                    

DEPOSIT INFORMATION

Inbred seeds of LH263 have been placed on deposit with the American TypeCulture Collection (ATCC), Rockville, Md. 20852, under Deposit AccessionNumber 97819 on 6 Dec., 1996. The deposit of inbred LH263 consists of2500 seeds. A Plant Variety Protection Certificate is being applied forwith the United States Department of Agriculture.

Although the foregoing invention has been described in some detail byway of illustration and example for purposes of clarity andunderstanding, it will be obvious that certain changes and modificationsmay be practiced within the scope of the invention, as limited only bythe scope of the appended claims.

What is claimed is:
 1. Inbred corn seed designated LH263, having ATCCaccession No.
 97819. 2. A corn plant produced by growing the seed ofclaim
 1. 3. Pollen of the plant of claim
 2. 4. An ovule of the plant ofclaim
 2. 5. An inbred corn plant having all the physiological andmorphological characteristics of the inbred corn plant of claim
 2. 6. Acorn plant regenerated from a tissue culture of tissue obtained from thecorn plant of claim 2, said regenerated corn plant having capable ofexpressing all the physiological and morphological characteristics ofsaid corn plant of claim
 2. 7. A method for producing first generation(F₁) hybrid corn seed comprising crossing a first inbred parent cornplant with a second inbred parent corn plant and harvesting theresultant first generation (F₁) seed, wherein one but not both of saidfirst inbred parent corn plant and said second inbred parent corn plantis the corn plant of claim
 2. 8. The method of claim 7 wherein said cornplant is the female parent.
 9. The method of claim 7 wherein said cornplant is the male parent.
 10. Hybrid seed produced by crossing a firstinbred parent corn plant with a second inbred parent corn plant andharvesting the resultant hybrid seed, wherein one but not both of saidfirst inbred parent corn plant and said second inbred parent corn plantis the corn plant of claim
 2. 11. Hybrid corn plants grown from thehybrid seed of claim 10.